In general image realization process, image data are loaded at a CPU (Central Processing Unit), and the loaded image data are rendered at a GPU (Graphics Processing Unit). Like above, since the GPU may render only the loaded image data, image data first loaded, first rendered.
Generally, a conventional resource loading method determines a loading order of an object on the basis of the virtual distance between a particular point and the object from image data. In case that the particular point moves, a new object necessary for rendering is loaded in order of the nearest virtual distance, on the basis of the newly computed virtual distance between the particular point and the object.
Even in case that a recording device records all image data with respect to objects constituting a particular virtual space, there is a case that some objects are not displayed on images rendered and generated by the GPU. Taking a game as an example, although a tree object for indicating a tree is positioned near from a location of a player character, in case that a big building object is provided between the player character and the tree object, the tree object may not be seen at all in the visual field of the player character.
In this case, the GPU does not render the tree object, unless the player character moves to the back of the building object. Thus, the tree object is not displayed on a display unit, however, since the tree object is near to the player character, the CPU “loads the tree object prior to an object that is positioned further away from the player character than the tree object, but has to be rendered”.
That is, according to the prior art, there is a problem that the CPU first loads an object unnecessary to be displayed to a user rather than other objects necessary to be displayed to the user, just because the virtual distance between the object and a player character is nearer than other objects.